Question 1135654
Let {{{ C }}} = cost of printing a book
Let {{{ n }}} = the number of pages
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Company A:
(1) {{{ C = 40 + 1.25n }}}
Company B:
(2) {{{ C = 25 + 1.3n }}}
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(a)
{{{ n = 160 }}}
(1) {{{ C = 40 + 1.25*160 }}}
(1) {{{ C = 40 + 200 }}}
(1) {{{ C = 240 }}}
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(2) {{{ C = 25 + 1.3*160 }}}
(2) {{{ C = 25 + 208 }}}
(2) {{{ C = 233 }}}
Company B is cheaper
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(b)
Set both costs equal
{{{ 40 + 1.25n = 25 + 1.3n }}}
{{{ .05n = 15 }}}
{{{ n = 300 }}}
For 300 pages the costs are the same
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check:
(1) {{{ C = 40 + 1.25*300 }}}
(1) {{{ C = 40 + 375 }}}
(1) {{{ C = 415 }}}
and
(2) {{{ C = 25 + 1.3*300 }}}
(2) {{{ C = 25 + 390 }}}
(2) {{{ C = 415 }}}
OK